Hi,
if I enable ONLY the hikashop recaptcha V2 plugin, recaptcha works as expected, but only in the registration form.
if I enable ONLY the joomla recaptcha plugin, recaptcha works as expected, but only in the joomla contact form.
if I enable both plugins, recaptcha works as expected in the hikashop registration form. However in the contact form, the recaptcha field is not showing. If I click the contact form send button, I get the joomla error message "Error Empty solution not allowed". The form is not sent.

Joomla Global Configuration / site settings / default captcha is set to "captcha - recaptcha". This is also the only available option (except "none", of course)

my question: How do I set up joomla/hikashop, so that I can have a recaptcha check in both the registration form and the contact form at the same time?

Never mind, I found the solution.
- Disable the joomla recapture plugin.
- in the hikashop plugin, enable "use in contact forms"
joomla global configuration / site settings / default captcha is set to none.

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